Tilt macro lens for Sony NEX cameras

I reckon there are easier solutions, but the most complicated one I could find is this one.

I bought a Sony NEX-5 (obvious), then an adapter to fit Bronica SQ lenses onto Nikon bodies, then theLensbaby to mount Nikon lenses, with TILT, onto NEXes, and finally a Nikon extension tube – but I also have a Bronica SQ extension tube: I could use either!

The result is that I can use my Zenzanon 150mm as a macro tilt lens. The first example is on iStock.

Now, there is one problem. Normally, when you take a lens detached from its camera, and you set the aperture to less than the maximum, the aperture closes: as you can imagine this is very convenient on the NEX, since its LCD adapts the brightness automatically. However, I noticed that with Bronica SQ lenses the opposite happens: the detached lens (and therefore the lens mounted on my adapter) stays at the maximum aperture, not ideal for macros. I want to keep it closed, I must operate manually the D.o.F. preview slider button on the lens. This is not nice because vibrations are amplified and my touch is not gentle!

So, clearly, a cleaner solution would be attaching on the Lensbaby a Nikon F-mount lens (like my fantastic Tamron SP 90/2.5). However, this solution is almost neat and it looks nowhere as monstrous as the other Bronica solution.

P.S.: I have received a perfectly working solution in a photo.net's forum post.